Symphony Center is a music complex located at 220 South Michigan Avenue in the Looparea of Chicago, Illinois. Home to the Chicago Symphony Orchestra, Chicago Symphony Chorus, Civic Orchestra of Chicago, Chicago Sinfonietta, and the Institute for Learning, Access, and Training, Symphony Center includes the 2,522-seatOrchestra Hall, which dates from 1904; Buntrock Hall, a rehearsal and performance space; Grainger Ballroom, an event space overlooking Michigan Avenue and the Art Institute of Chicago; a public multi-story rotunda; tesorirestaurant; and administrative offices. In June 1993, plans to significantly renovate and expand Orchestra Hall were approved and the $110 million project resulting in Symphony Center being completed from 1995 to 1997. Orchestra Hall at Symphony Center was designated a National Historic Landmark on April 19, 1994.[1]It has been listed on the National Register of Historic Places since 1978.

History
Built in 1904, Orchestra Hall was designed by renowned Chicago architect Daniel Burnham. The new hall was specifically designed as a home for the Chicago Symphony Orchestra, which had previously performed in the larger Auditorium Theater. Construction began on May 1, 1904 and the first concert was held on December 14, 1904. The building has "Theodore Thomas Orchestra Hall" inscribed in its façade, after the orchestra's first music director who died less than a month after his conducting debut there. The namesBach, Mozart, Beethoven, Schubert, and Wagner are inscribed above the ballroomwindows on the façade.

From 1907 through 1996 the ninth-floor penthouse of the building served as the home of the Cliff Dwellers Club, with interior architecture by Howard Van Doren Shaw and the first significant mural of John Warner Norton.
Orchestra Hall was also used as a movie theater during the 1910s, to maintain income during the summer months, when the Chicago Symphony Orchestra was playing at the Ravinia Festival. Lectures and other programs were held at Orchestra Hall in the 1920s and 1930s, with speakers including Harry Houdini,Richard E. Byrd, Amelia Earhart, Bertrand Russell and Orson Welles.

Acoustical problems
Suboptimal acoustics within Orchestra Hall have been an ongoing concern throughout its history, and have been adjusted in major overhauls of the main hall in both the 1960s and as part of the Symphony Center transformation between 1995 and 1997.[4] Critics have said that the acoustical revamping created more problems than it solved, compromising the quality of the sound patrons had known for generations.

The original acoustical consultant, R. Lawrence Kirkegaard, spent six seasons fine-tuning the hall. Former CSO President Henry Fogel, at whose behest more than 50 percent of Burnham's original interior was lost forever, admitted that the revised acoustics of the auditorium are flawed, and brought in acoustician Russel Johnson to render a second opinion.[5][6] Prominent Chicago critics have bemoaned the "recklessness of making irreversible changes to the structure of the hall"